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macrumors bot
Original poster
Apr 12, 2001

Earlier this week, do-it-yourself repair website iFixit shared its full teardown of the new 16-inch MacBook Pro, providing a closer look at its scissor switch keyboard, new thermal architecture, and other design tweaks.

As it turns out, there is one more change. In an internal document to Apple Authorized Service Providers, obtained by MacRumors, Apple indicates the 16-inch MacBook Pro includes a new "lid angle sensor" that presumably monitors the opening and closing of the notebook and the precise position of the lid.

MacRumors reached out to iFixit to investigate, leading them to uncover a small sensor facing the left-side hinge of the notebook. There is also a magnet embedded in the hinge itself, with an arrow indicating polarity. iFixit has updated its teardown with photos of the sensor, which we've shared below.

Photo: iFixit

While previous-generation MacBook Pro models have a Hall effect sensor that determines when the lid is closed for sleep/wake purposes, the lid angle sensor in the 16-inch MacBook Pro appears to be more sophisticated.

Apple's service document does not provide any clues as to why the sensor was redesigned, but iFixit speculates that it could provide a clever way for Apple to track how often the lid was opened, closed, or adjusted in cases where the display or frayed flex cables need to be repaired -- think "Flexgate."

Photo: iFixit

The lid angle sensor could also be for an unannounced macOS feature, although again, this is merely speculation.

Of note, in the event of a display repair, Apple's service document indicates that technicians must calibrate both the display and the lid angle sensor in order for the repair to be considered complete. If we learn any additional information about the sensor, we will be sure to provide an update.

Article Link: 16-Inch MacBook Pro Features New 'Lid Angle Sensor'
Last edited:


macrumors 6502
Jun 8, 2017
Lots of cabinets and drawers have magnetic hardware to give them a more "premium" feel, so the polarity could be for that or even to hold the lid closed when shut. Standing by for a youtube shootout comparing the best sounding laptop lid snaps...


macrumors member
Dec 31, 2017
My 2015 MBP has a magnetic sensor on the left side. My TI2 pen has magnets to hold the cap on. One day I placed my pen next to my laptop and the screen shut off because the magnet caused it to think the lid was closed.

My coworker has a 2018 MBP that does not respond to the pen. However, when he disconnects from his external monitors with his laptop screen up, his computer will completely lockup, as if it thinks the lid is closed. Opening it and closing it has no effect, and the trackpad goes completely dead (no haptic - just like my laptop when the pen is placed beside it).

My theory: I know other people with the same issue when disconnecting from hubs/docks. I guarantee more than a few have gone to the Genius Bar about this issue. This sensor is so the machine knows if the display is actually closed or not so it does not lock up for those and similarly-affected users.


macrumors 6502
Apr 3, 2011
Maybe this could be used for the speakers and/or microphone so that they can be better calibrated when the lid is half-closed.

edit: got ninja’d...
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macrumors 6502a
Aug 4, 2017
San Diego, CA
Or maybe the screen has an electro-sensitive coating that destabilizes under voltage, providing a matte finish to the screen. The software adjusts the reflectiveness of the screen based on screen angle and ambient light to provide the best balance of image and anti-glare! /s

Seriously, I'm sure it's one of the incredibly un-sexy items mentioned in the article.

Clocking lid openings?
Sounds about right.
Might simply because they couldn't fit large enough magnets with the new smaller bezels.
There we go. I'm changing my answer to terraphantm's.
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macrumors newbie
Nov 19, 2019
Anyone have any idea what sensor this is? I have never seen a sensor that small that can measure angle like that is doing.


macrumors regular
Oct 18, 2013

Flight Plan

macrumors 6502
May 26, 2014
Southeastern US
This is probably the "pervert privacy protection" feature. If it senses the lid closing super rapidly, it closes all browser windows and scrubs the hard drive of all your porn.
Okay, I know everybody else is laughing at that. Or they're closing their laptops super rapidly. :p

Mr. Awesome

macrumors 6502a
Feb 24, 2016
Idaho, USA
I'm an Apple technician an AASP and we have been speculating about this since the internal documents were released.

The leading theory at this point is that it gathers info about whether the screen has been over extended at any point leading to hinge damage.

You’re probably right.

But seriously, some of the ideas we’re coming up with here are hilarious and probably outlandish.
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macrumors member
Sep 12, 2017
The leading theory at this point is that it gathers info about whether the screen has been over extended at any point leading to hinge damage.

or to determine if the users, of units sold in Japan, are trying to grab those upskirt shots. oh wait, it's a crappy 720p cam. nevermind.
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macrumors member
Sep 14, 2012
Love the dock/hub undock theory, Seems excessive to have a sensor for this. This issue sure is annoying when eveything is non responsive after connecting to external monitors....only keyboard lights are active....
Case closed folks
I see what you did there ?
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macrumors newbie
May 13, 2019
I'm an Apple technician an AASP and we have been speculating about this since the internal documents were released.

The leading theory at this point is that it gathers info about whether the screen has been over extended at any point leading to hinge damage.

Yes, I somehow managed to damage my 2016 MBP 13" — and I am careful. There is no way to limit how far the screen can go back.
IMG_4228 2.jpg
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